In a galvanometer the tangents of the angles of deflection of the needle are proportional to the deflecting force– I.  When the controlling force is unaltered in absolute magnitude and direction by the motion of the needle. II. When the deflecting force acts at right angles always to the controlling force. These conditions are usually [...]

Reduced nitro-cellulose. Nitro-cellulose is dissolved in a proper solvent and is obtained by evaporation as a translucent solid mass. By ammonium sulphide or other reagent it is reduced so as to be virtually cellulose. It is cut into shape for filaments of incandescent lamps, which shapes are carbonized and flashed.

Symbol of time.